Collaborative Research: How is Strain of the Eastern California Shear Zone Transferred Across the Garlock Fault?

相交断层系统的相互作用可能是复杂的，并可能导致复杂的变形和覆盖在所有尺度上的结构。在这方面，一个特别令人感兴趣的地区是加利福尼亚东部，那里是加利福尼亚东部剪切带（ECSZ）和加洛克断层相交的地方。东南亚是一条100公里宽的北西北走向走滑断裂带，其类型和走向与圣安德烈亚斯断层相似；加洛克断裂是一条运动方向相反的大致东向走滑断裂。加洛克是贯通的，而ECSZ的断层似乎在接近加洛克时就结束了。虽然Garlock看起来是更连续的结构，但GPS和卫星信息似乎表明，与ECSZ相关的变形持续地穿过它。该项目正在研究这两个系统如何在介观和宏观尺度上相互作用。特别是，与这两个构造系统相关的断层和褶皱领域的制图旨在评估东南亚断层是否确实在到达加洛克之前结束（如果是的话，如何结束）。地图也显示了加洛克河是否像之前认为的那样是连续的。还收集了样品，以确定各种偏移地形和地表特征的年龄。这提供了每个断层移动的速率。该信息补充了显示故障如何结束的映射，因为运动损失可以与运动速率相关联。在某些地方，探地雷达被用来成像断层在地下的走向。这些信息对于评估运动速率也很重要。通过收集所有这些不同类型的信息，该项目试图详细了解ECSZ和Garlock的相互作用，从而确定复杂断层区域的地壳是如何变形的。这对于理解北美西部地壳的整体变形是至关重要的。

The interaction of intersecting fault systems can be complex and can lead to complicated deformation and overprinting on structures at all scales. An area of particular interest in this regard is in eastern California where the Eastern California shear zone (ECSZ) and the Garlock fault intersect. The ECSZ is a 100 km wide belt of north-northwest trending strike-slip faults of similar type and orientation as the San Andreas fault; the Garlock fault a roughly east trending strike-slip fault of opposite sense of motion. The Garlock is through going whereas faults of the ECSZ seem to end as they approach the Garlock. Although the Garlock appears to be the more continuous structure, GPS and satellite information seem to show that deformation related to the ECSZ passes continuously across it. The project is investigating how these two systems interact at mesoscopic and macroscopic scales. In particular, mapping in the field of faults and folds related to both structural systems is aimed at assessing whether faults of the ECSZ do indeed end (and if so how) before reaching the Garlock. Mapping is also showing if the Garlock is as continuous as previously thought. Samples are also being collected to determine the ages of various offset landforms and surface features. This provides the rate at which each fault is moving. This information complements the mapping showing how the faults end in that the loss of motion can be correlated with the rates of motion. In some locations, Ground Penetrating Radar is used to image how faults are oriented in the subsurface. This information is also critical to assess the rates of motion. By the collection of all these different types of information, the project is attempting to understand in detail the interaction of the ECSZ and Garlock and thus determine how the crust of the earth deforms in areas of complicated faulting. This is critical to understanding the overall deformation of the crust in the western part of North America.